TypeScript学习记录

基础类型

数字 number

const level: number = 6

字符串 string

cosnt name: string: "huangping"

布尔值 boolean

const isBoy: boolean = true

数组 array

const list: number[] = [1, 2, 3]

元组 Tuple

let x: [string, number];
x = ['hello', 10]

枚举 enum

enum Color { Red, Green, Yellow }
let c: Color = Color.Green;

任意值 any

let a: any = 4
a = 'huangping'

空值 void

function voidFunc(): void {
    console.log('void')
}

Null和Undefined

Never

类型断言

let someValue: any = "this is a string";
let strLength: number = (<string>someValue).length;
or
let strLength: number = (someValue as string).length;

接口

用interface关键字定义一个接口

• 当接属性可选时，可在属性名字定义后面加上一个?符号
• 只读属性，可在属性名前用readonly来指定

interface person {
    name: string;
    age: number;
    address?: string;
    readonly sex: string;
}